title: Culture expansion induces non-tumorigenic aneuploidy in adipose tissue-derived mesenchymal stromal cells.
abstract: OBJECTIVE
  Adipose tissue-derived mesenchymal stromal cells (ASCs) are of interest as a cell therapeutic agent for immunologic and degenerative diseases. During in vitro expansion, ASCs may be at risk for genetic alterations, and genetic screening is a prerequisite. We examined the presence of aneuploidy in ASCs and its origin and development during culture and evaluated the implications of aneuploidy for therapeutic use of ASCs.
  
  
  METHODS
  Adipose tissue of healthy individuals was used for isolation and expansion of ASCs. Chromosome copy numbers were studied using fluorescence in situ hybridization analysis. Aneuploidy was studied in freshly isolated ASCs, in ASCs cultured for 0-16 passages and in senescent cultures. To evaluate the plasticity of ploidy, ASCs were cloned, and the variation of ploidy in the clones was examined. Tumorigenicity was studied by subcutaneous injection of aneuploid ASCs in immunodeficient NOD/SCID mice.
  
  
  RESULTS
  No aneuploidy was detected in freshly isolated ASCs. In low passages (passages 0-4), aneuploidy was detected in 3.4% of ASCs. Prolonged culture expansion of ASCs (passages 5-16) resulted in a significant increase of aneuploidy to 7.1%. With senescence, aneuploidy increased further to 19.8%. Aneuploidy was observed in clones of diploid ASCs, demonstrating the de novo development of aneuploidy. No transformation of ASCs was observed, and in contrast to cancer cell lines, aneuploid ASCs were incapable of tumor formation in immunodeficient mice.
  
  
  CONCLUSIONS
  ASC cultures contain a stable percentage of aneuploid cells. Aneuploidy was not a predecessor of transformation or tumor formation. This finding indicates that aneuploidy is culture-induced but unlikely to compromise clinical application of ASCs.
authors.affiliation: Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands. Electronic address: m.vanrhijn@erasmusmc.nl.
authors.forename: Marieke
authors.initials: M
authors.lastname: Roemeling-van Rhijn
authors.forename: Annelies
authors.initials: A
authors.lastname: de Klein
authors.forename: Hannie
authors.initials: H
authors.lastname: Douben
authors.forename: Qiuwei
authors.initials: Q
authors.lastname: Pan
authors.forename: Luc J W
authors.initials: LJ
authors.lastname: van der Laan
authors.forename: Jan N M
authors.initials: JN
authors.lastname: Ijzermans
authors.forename: Michiel G H
authors.initials: MG
authors.lastname: Betjes
authors.forename: Carla C
authors.initials: CC
authors.lastname: Baan
authors.forename: Willem
authors.initials: W
authors.lastname: Weimar
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Hoogduijn
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000328:Adult; D000368:Aged; D000782:Aneuploidy; D000818:Animals; D002454:Cell Differentiation; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D064987:Cell- and Tissue-Based Therapy; D002478:Cells, Cultured; D016922:Cellular Senescence; D002999:Clone Cells / Q000166:cytology; D005260:Female; D042822:Genomic Instability / Q000235:genetics*; D006801:Humans; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D051379:Mice; D016513:Mice, SCID; D008875:Middle Aged
keywords: adipose tissue; aneuploidy; clinical application; mesenchymal stromal cell; senescence; transformation